Give me back that filet-o-fish, give me that fish. What if it were you hanging up on this wall? If it were you in that sandwich, you wouldn't be laughing at all.

Sung by a blue, wall-mounted fish, the jingle comes from a McDonald's ad, one Liz Gumbinner's daughters, two-and-a-half-year old Sage and four-and-a-half-year old Thalia, know by heart.

The girls also like Kia Sorento ads - the ones with the giant sock monkey - and know the Disney castle logo because it appears at the start of their DVDs.

"Right now, thanks to commercials, they're asking for a trip to Disney World, the new Tim Burton
Alice in Wonderland movie and a bunk bed [from]the Pottery Barn catalogue, complete with
Star Wars sheets. Also, those old horrible recalled Aqua Dots, because the ads are saved on DVR with some old episodes of
Yo Gabba Gabba," says Ms. Gumbinner.

The New York-based freelancer calls it karma: She makes ads. Ms. Gumbinner has worked for Cabbage Patch Kids, Universal theme parks, Old Navy, Foot Locker, Ray Ban and Mitsubishi.

Although Ms. Gumbinner isn't surprised, parents may be cautioned by new research that suggests children as young as three recognize brands and what they symbolize, a much younger age than was previously theorized - seven and eight.

The study, published yesterday in the journal Psychology & Marketing, found that children between the ages of three and five show an "emerging ability" to use ads to judge which products will be the most "fun" and make them popular - even though they can't read yet.

"Not only do they understand what the brand is, they understand that this is something they can use in their day-to-day lives. Their understanding helps them to negotiate the environment," says study author Bettina Cornwell, a professor of marketing in sport management at the University of Michigan.

In the first part of the study, the researchers showed 38 children logos for 50 brands as disparate as Coca-Cola, Looney Toons and Band-Aid and asked, "Have you seen this before?" and "What types of things do they make?" as well as other questions about the products' value.

The average recognition rate was 39 per cent, and the most commonly recognized brand was McDonald's (93 per cent), followed closely by toys such as Lego (75 per cent) and soda products.

Fast food was described by the three to five-year-olds as "fun, exciting and tasty." Cola brands were fun because "the bubbles are fun" and "lots of people like them."

The researchers also showed another 42 children a board featuring brand logos, including McDonald's, and asked them to pick out images associated with the company - a French fry box, "drive thru" sign and Hamburglar. Many children could match the images with the logo, probably because they'd seen it each time they dug into a Happy Meal or pulled up at the restaurant, Prof. Cornwell believes.

"There's a ton of branding specifically designed for that pre-school audience," says Josh Golin, associate director of Campaign for a Commerical-Free Childhood, a Boston-based organization that raises awareness about kids' marketing.

"Obviously, a customer formed at that age is worth more to a brand."

Prof. Cornwell and her co-authors want lawmakers to take a closer look at fast food branding aimed at young children.

"From a policy perspective, we need to recognize that this is not being lost on the very young. The under-six, under-seven, under-eight crowd is very capable of understanding brand messages and utilizing brand information in their lives."In the UK, laws prevent companies from advertising during times of day when children are most likely to watch television. In Quebec, laws prohibit advertisers from marketing to children under the age of 13. The law looks at "the nature and intended purpose" of the goods advertised and the time and place the ad is shown.

Although Ms. Gumbinner believes some industry regulation is needed, she says the "ultimate gatekeepers" are parents, not advertisers.

"My [daughter]cannot walk herself to the McDonald's and buy a Big Mac without my help," says Ms. Gumbinner, who is also editor-in-chief of CoolMomPicks.com, a shopping and design blog for parents.

Thanks to Ms. Gumbinner's occupation, her children have the inside track: "I tell them that my job is to write commercials, that there are people writing those things, and that our job is to get people to like the product. And that that's why they need to get information about those products from places other than the commercials. They understand that."

Still, label-consciousness and cable-control aside, parents acknowledge that the final say often lies with their children's peers at daycare or kindergarten.

Prof. Cornwell recalls the day her four-year-old son David came home from preschool and demanded Pokémon cards: "I just know I need to have some." .

"Other children had them and, in order to be involved, he needed to have some."